Die for drill-sharpening machines



March 18,11924. 1,487,16o

A. A. HEN'rzELL w DIE'FOR DRILL SHARPENING MAGHINES File .inne so. 1922 I l l' IfTINVENTOR I JM' .ms ATToR EY Patented Mar. 18, 1924.

FFICE.

ALFRED A. HENTZELL, or LITTLETON, coLoRAno, AssIGNoa To INGERsoLL-RAND COMPANY, or JER-SEY CITY, NEW JERsnY, A ODBI'OBATION onNEW JERSEY.

DIE FOR DRILL-SHARPENING MACHINES.

Application filed June 30, 1922. Serial No. 571,882.

To all whom it may concern:

Be it known that LALFRED A. HENTZELL, a citizen of the United States, and a resident of Littleton, county of Arapahoe, 6 and State of Colorado, have invented la certain Die for Drill-Sharpening Machines,'of

which the following is a specification' accompanied by drawings.

This invention relates to drill sharpening 10 or forging machines and particularly to upsetting and forming dies used in such machines for imparting a desired conformation to the ends of rock drill steels, such, for instance, as required in forming collars or lugs.

A forging or drill sharpening machine of the type adapted to form lugs or collars on rockV drill steels is shown in my prior. Patent No. 1,223,975 granted April 24, 1917,

wherein the main holding di-es which are fitted to the stationary and movable jaw members in the machine to adapt the machine for the purpose mentioned, also act as bushings and receive the impact of the percussive element i'ncident to the operation of upsetting the end of;v the drill steel. Hence, these dies are directly' subject to shock and wear rapidly, necessitatin'g complete replacement when deformed.l This is expensive and otherwise unsatisfactory.,

The primary object of the present invention is to enable the bushings which bear the shock and wearin theforming operations to be easily, quiclrly and cheaply replaced or renewed,v without' replacing or renewing the main holding dies or affeoting their adjustment in any way.

Another objectv is to retain the b'ushings and plunger dies in the main holding dies against unintentional displacement. VVVA further object is to enable the removable bushings and plunger dies to cooperate in defining the forming recess. Still further objects will later appear and to all the ends herein set forth the invention consists in the features of construction and operation described in the following specification and illustrated in the accompanying drawings, forming a part hereof, in which- Figure 1 is a side elevation partly in section of a drill sharpening machine embodying the invention;v

Figure 2 is an enlarged detail longitudinal sectional View of the main holding dies and forming'dies;

Figure 3 is a transverse sectional view taken on the line 3-3 ofFigure';

F igure 4: is a perspective View of one of the main holding dies; and j Figure 5 is a perspecti've. View of oneof the removable bushings.

Inthe drawings the invention is shown' in connection with a drill sharpening machine.

which in its essential characteristics is similar to the machine illustrated in m'y prior patent referred to. The drill sharpening machine includes a base A supporting a stationary lower clamping jaw B and a movable upper clamping jaw O, the jaw C being mounted on a vertically reciprocable plunger (not shown). An arm D extends from the Vbase and a percussive element in the form of a pneumatically actuated tool E is adapted to be mounted on the arm D, so that the reciprocable dolly F is in alignment with the space between the` opposing surfaces of the jaw members B and O. The jaws B and C are adapted to be brought close. together for performing various operations upon the drill steel. w cutting or severing the lengths of drill steel, and for this purpose cooperating cutters G are secured on the'jaws B and C at the front of the machine, by bolts H.

Upper and lower die holder ;guides or seats J' are fitted over the opposing surfaces of the jawsB and O. These seats are provided with offset portions K and turned ends VL, and are adapted to be inserted in the jaws and C so that the rearwardly inclined Shoulders O on4 the seats J abut against similarly inclined Shoulders `P on the jaws, thus vrigidly securing the seatsJ against longitudinal movement in the direction opposite to the percussive tool E. The turned eiids L are sec-ured to the jaws B and C'by bolts Q.

The inner opposingsurfaces R and S of the die seats J in the jaws B and C respectively, are semi-circular and together form a longitudi'nal circular recess, for 'receiving and retaining' the longitudinal main holding dies and forming dies in place between the jaws B and C. The main. holding dies T are approximately semi-circular in'cross section, the outer surfaces U being provided One such operation is that of ice with webs or fianges V having inclined sides which iit sen'ii-circular undercut recesses lV in the opposing die seat surfaces R and S. The main holding dies T are thus retained in the die seats J against longitudinal movement, and the main holding dies in turnretain the forming dies, which include bushings and plunger dies.

The inner surfaces of the main holding dies T form longitudinal semi-cylindrical grooves or recesses Y and at the sides of these Vgrooves Y are longitudinal beveled Vribs Z.

A pair of removable semi-cylindrical bushings a are adapted to be inserted longitudinally in the recesses Y, these bushings a being cut away at their longitudinal outer sides as shown at in correspondence with the beveled ribs Z in the recesses Y, so that the bushings are retained in the recesses Y against Vertical or transverse movement. Looking pins (Z are adapted to pass through centralholes e in the main holding dies T and into corresponding holes or recesses f in the bushings a to hold the bushings against longitudinal movement. For a portion of their length the busnings a are provided with opposite longitudinal recesses g which are adap'ted to effect clamping engagement with the shank of a drill steel 77. Adjacent to one end, however, the recesses g are enlarged so that together they form an upsetting recess h. Swaging means I are adapted to coope-rate with the bushings a. In the present instance thev swaging means comprise a pair of upper and lower plunger dies 7' adapted to be inserted longitudinally within the recesses Y of the main 'holding dies T in the same manner as the removable bushings a, but such swaging means I may consist of a single plunger die or may be otherwise formed. The bushings a and swaging means I constitute the forming dies for imparting the desired conformation to the end of a rock drill steel or other article. The plunger dies j are of relatively less length than the bushings a and have opposite internal recesses 7a extending longitudinally for a portion of their length adapted to accommodate the sides of the end of the drill steel 77, the extreme end of the drill steel p abutting against the Shoulders Q within the plunger dies j, The inner ends of the plunger dies y', the recesses 73 and the outer walls of the upsetting recess h are adapted to cooperate and act as forming surfaces and recesses for the purpose set forth herein. In the present instance the forming dies are adapted to forge a lug or collar adjacent to the end of a drill steel shank. .The drill steel is securely held between the bushings a and plunger dies r7' when the aw member C is lowered, the steel having first been heated and inserted the required distance. The percussive tool E is then operated to cause the dolly F to recipro- Cate rapidly against the outer .ends of the swaging means I in this case the plunger dies j, forcing the metal into the upsetting recess lt, the walls of which recess h are defined by the adjacent ends of the bushings a and swaging means I, and the lug or collar is formed on the steel under the swaging pressure administered through relative movement of the forming dies. i

In assembling the dies the bushings a are inserted longitudinally in the recesses Y of the main holding dies T to the limit of their movement against Shoulders r and the pins d are passed through the aligned holes e and recesses f. The plunger dies j are similarly inserted, but are freely movable longitudinally. The main holding dies T are then held so that the webs V are aligned with the recesses `W in the die seats J and are then slid transversely into place in the die seats, the movable jaw of the sha-rpener having first been raised to its uppermost position. When thus inserted the outer edges of the bushings, main holding dies and die seats in each group are in parallel alignment and form plane opposing surfaces.

The points of rapid and greatest wear in a machine of the Character described are the surfaces of the bushings which are subject to the swaging pressure exerted by the plun ger dies under the influence of the percussivel tool. When such bushings are integral with the main holding dies, or when the bushing surfaces are formed on the main holding dies themselves, as in my prior patent referred to, it becomes necessary to replace the maiil` holding dies at more or less frequent intervals. This is anv expensive proceeding which the use' of separate removable bushings as shown, described and claimed herein` avoids. The bushings are comparatively in eXpensive and a supply can be kept on hand so that no time is lost in the operation of ths` machine.

I claim:

1. In a drill sharpener, a pair of relatively movable jaws, die holder guides fitted over the opposing surfaces of said jaws, holding dies in said guides, said guides and holding dies having cooperative fianges to retain the holding dies in the guides, a pair of die bushings in said holding dies, a pair of plunger dies slidable in said holding dies, longitudinal ribs to retain saidbushings and plunger dies Within said holding dies, and locking pins adapted to pass through said holding dies to hold the bushings in a fixed position with relation to said holding dies.

V2. In a drill sharpener, the combination of relatively stationary and movable jaws, cooperating main holding dies carried by said jaws, and forming dies in said holding dies adapted to aot on a drill steel, said forming dies including a pair of upper and lower` semi-circular bushings longitudinally insertable and slidable in said holding dies and adapted to effect olamping relationship With said drill steel, a pair of cooperating semicircular plunger `dies slidable in said holding dies and adapted to fit over and abut against the end of a drill steel held between said bushi'mgs,` and looking pins passing through said main holding dies into said bushings, said bushings being provided With recesses corresponding to the form of collar desired to be upset on the shank of the 10 drill steel, and said plunger'dies having forming surfaces cooperating therewith.`

In testimony Whereof I have signed this` specification.

ALFRED A. HENTZELL. 

